Riddle

Here is one tough riddle. Only the cleverest and smartest of you will be able to solve it. Ready to show me that you are the smartest? Have a go!
My first is in Dinosaur, but not in saurian,
I am second and next to last
Four and six are 0,
But third is 14th.
Tea is at 5,
And the first of party is seventh.
And the last is first, like the third.

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